In attempting to determine a rapid and accurate method for the etiologic diagnosis of a given case of endophthalmitis we propose to undertake the following investigations: A. To complete the glucose study correlating the levels of aqueous glucose with those of the blood. B. To develop antibodies to many more bacteria within animals and to adapt their use to the technique of counter immunoelectrophoresis. C. To attempt to determine the possibility of a more rapid identification of bacteria using the filtrate of the aqueous following passage of this material through a millipore filter.